March 14 is my favorite day to be a nerd .

Across the country , math geeks in museums , schools , private groups and elsewhere gather to celebrate the number pi , approximately 3.14 . That 's why March 14 -- 3-14 -- is Pi Day . What 's more , Albert Einstein was born on this day .

A quick refresher : Pi is defined as the distance around a perfect circle , or the circumference , divided by the distance across it , or the diameter . It is also involved in calculating the area of a circle , the volume of a sphere , and many other mathematical formulas you might need in the sciences .

Throughout history , people have been captivated by this number because there is no way to calculate it exactly by a simple division on your calculator . What 's more , its digits go on infinitely , without any pattern in the numbers . 3.1415926535897932 ... etc. . Even that many digits are more than most people would need for everyday use , but some folks have been inspired to memorize thousands of digits of pi , or even use the digits to create poetry or music .

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Math may be scary , but pi is not -- as evidenced by the widespread revelry on Pi Day . One might even say -- gasp ! -- it 's cool to like pi these days . Even the House of Representatives supported the designation of March 14 as National Pi Day in 2009 .

In countries where the day is written before the month , Friday is 14-3 , which looks less like pi . `` And so Pi Day is an acquired taste , '' mathematician Jonathan Borwein , at the University of Newcastle in Australia , said in an e-mail .

Conveniently , `` pi '' sounds like `` pie , '' and pies are round . You could celebrate Pi Day in a casual way by grabbing a slice of pastry , or pizza . If you 're in enrolled in school , your math class or math department might be doing something special already .

But if you happen to live in a particularly pi-happy place , you might be able to take part in some larger-scale , pi-inspired activities .

Where Pi Day began

If you want to go where the day is said to be `` invented , '' look no further than San Francisco 's Exploratorium . Larry Shaw , who worked in the electronics group at the museum , began the tradition in 1988 . Last year was Pi Day 's 25th anniversary there .

Pi Day began as a small gathering with mostly museum staff . Now it 's a public pi extravaganza featuring a `` Pi procession , '' whose attendees get a number -- 0 to 9 -- and line up in the order of pi 's digits : 3.14159265 ... you get the idea .

The parade ends at the `` pi shrine '' -- a pi symbol with digits spiraling around it embedded in the sidewalk , which was unveiled last year .

For those who ca n't attend in person , the Exploratorium has a Second Life Pi Day event that includes `` irrational exhibits , fireworks , cheerleaders , music , and dancing . '' The museum also lists a bunch of educational activities to teach about the concept of pi .

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Where Einstein lived

On the opposite coast , the leafy university town where Albert Einstein spent the last 22 years of his life is showing community-wide exuberance for pi .

Princeton , New Jersey , kicks off Pi Day weekend on Thursday night with a reading by physicist Charles Adler , then heads into a full day of activities on Friday , including a walking tour of Einstein 's neighborhood and a pizza pie-making contest .

The pie-eating contest takes place at McCaffrey 's supermarket , while an Einstein look-alike competition will match mustaches and wild gray hair at the Princeton Public Library .

Pi fans who have been spending the last year memorizing digits can show off and compete at the library , where the winner among 7 - to 13-year-olds can take home a cool pi-hundred -LRB- That is , $ 314.15 -RRB- . The Historical Society of Princeton will have an Einstein birthday party . Tetsuya Miyamoto , inventor of the KENKEN puzzle , will speak at the library as well .

Here are 10,000 digits of pi for you to memorize

The `` brainiac town '' residents `` love this event because it 's a way for them to celebrate how quirky they are , '' said Mimi Omiecinski , owner of the Princeton Tour Company , who started Princeton Pi Day in 2009 . `` A lot of them get super into it . '' Last year about 9,000 people participated , she said .

Along with her fascination with Albert Einstein , Omiecinski was inspired to launch a town-wide Pi Day after she heard that the Princeton University mathematics department celebrates March 14 with pie-eating and pi-reciting -LRB- As a Princeton student , I got second place for most digits in 2005 and 2006 -RRB- .

Even more pi

Chicago is getting into the pi business too . Lots of restaurants and bakeries are offering Pi Day specials . The Illinois Science Council and Fleet Feet Sports are hosting a 3.14-mile walk/run Friday night , with discounts for anyone named Albert , Alberta or Albertina . Philly.com highlights two options for satisfying your pie cravings in the City of Brotherly Love .

Bostonians can head to Massachusetts Institute of Technology at Pi Time -LRB- 3:14 p.m. -RRB- for pi-themed activities such as `` Throw Pie at Your Best Friend on High-Speed Camera . ''

The Museum of Science in Boston has educational Pi Day events , and the Seattle Children 's Museum will celebrate too .

Even the Salvador Dali Museum in St. Petersburg , Florida , will celebrate the day , as `` Dali loved the irrational numbers Pi and Phi , often using them and other mathematical principles in his art , '' according to the museum . If you live in the area , check out their schedule of math-inspired films and tours throughout the day .

There are plenty of online resources too , such as piday.org .

Outside of the physical classroom , Pi Day will be celebrated online through Google 's virtual classroom project . David Blatner , author of the comprehensive book `` The Joy of Pi , '' is hosting a Pi Day competition in which students from three classrooms will square off to see who can recite the most digits of pi from memory .

How did Pi Day become such a big thing ?

Blatner says that Pi Day has become a hit for the same reason the new `` Cosmos '' TV show is getting so much attention .

`` People all around the world are hungry to make science and math fun and interesting , '' he said in an e-mail . `` We know math and science is important , we know that it 's fascinating , but we often do n't know how to make it fun and interesting . Pi Day gives us a great excuse to throw away our fear of math and say ` Hey , it IS kind of neat ! ' ''

If you agree , just wait until 3/14/15 -- or as one popular Facebook group calls it , `` The Only Pi Day of Our Lives . ''

That 's because pi to four digits after the decimal is 3.1415 , and we 're unlikely to survive until 2115 to see that second instance of pi perfection .

So get ready next year to take a picture of your digital clock on 3/14/15 at 9:26:53 a.m. That 'll be worth more than a thousand digits .

Follow Elizabeth Landau on Twitter at @lizlandau

How do you celebrate Pi Day ? Tell us in the comments .

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Math geeks and others celebrate Pi Day every March 14

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Pi , or roughly 3.14 , is the ratio of circumference to diameter of a circle

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The Pi Day holiday idea started at the Exploratorium museum in San Francisco

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Albert Einstein was also born on March 14